From: Rod Taylor <pg@rbt.ca>
To: Alison Winters <alison@mirrabooka.com>
Cc: pgsql-performance@postgresql.org
In-Reply-To: <42D5F34E.nail9QE1195IE@pluto.mirrabooka.com>
References: <42D5F34E.nail9QE1195IE@pluto.mirrabooka.com>
Date: Thu, 14 Jul 2005 12:37:42 -0400
Message-Id: <1121359062.780.31.camel@home>
Mime-Version: 1.0
Subject: Re: lots of updates on small table
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

On Thu, 2005-07-14 at 15:08 +1000, Alison Winters wrote:
> Hi,
> 
> Our application requires a number of processes to select and update rows
> from a very small (<10 rows) Postgres table on a regular and frequent
> basis.  These processes often run for weeks at a time, but over the

Are these long running transactions or is the process issuing many short
transactions?

If your transaction lasts a week, then a daily vacuum isn't really doing
anything.

I presume you also run ANALYZE in some shape or form periodically?

> space of a few days we find that updates start getting painfully slow.
> We are running a full vacuum/analyze and reindex on the table every day,

If they're short transactions, run vacuum (not vacuum full) every 100 or
so updates. This might even be once a minute.

Analyze periodically as well.

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